1. Field of the Invention
The invention relates to hearing aids which are intended to be placed in or on an ear. More particularly, the invention relates to the function of such hearing aids where a remedy for an occlusion problem is provided.
2. The Prior Art
In connection with hearing aids the occlusion problem is normally experienced by the user of the hearing aid when the hearing aid or the earmould of a hearing aid is introduced into the ear canal. The hearing aid user often experiences the occlusion effect as very uncomfortable.
In order to provide a remedy for the occlusion effect, a ventilation channel of a significant size may be provided in the hearing aid or in the earmould. However, providing an increased size vent often will have the effect of creating an acoustic feedback path. The size of the vent that may be created is therefore limited.
In the recent years feedback cancellation systems have been introduced for the purpose of eliminating or reducing acoustic feedback in normal hearing aid systems, i.e. with normal vent sizes, where the occlusion problem is present.
A first objective of the present invention is to provide a digital hearing aid where the occlusion problem is widely reduced.
A second objective is to provide a hearing aid where the occlusion problem is widely reduced and where at the same time a sufficient gain for the compensation of a hearing loss may be provided with reduced occurrence of acoustic feedback.
A third objective of the present invention is to provide a hearing aid system where the occlusion problem is widely reduced, where at the same time a sufficient gain for the compensation of a hearing loss may be provided with reduced occurrence of acoustic feedback.